Monomers for use in energy curable inks and coatings are well known. Sartomer, IGM, Allnex and others have been supplying a wide range of monomers for formulation. Many commonly used monomers are off patent and have been commoditized. There is very little innovation underway by the major suppliers of monomers and oligomers. Commonly used monofunctional monomers for UV curing include methoxy polyethylene glycol (550) monoacrylate, aromatic acrylate monomer, aromatic alcohols, alkoxylated lauryl acrylates, cycloaliphatic acrylate monomer, 2(2-ethoxyethoxy) ethyl acrylate, stearyl acrylate, acrylate ester, tetrahydrofurfuryl acrylate, lauryl acrylate, 2-phenoxyethyl acrylate, isodecyl acrylate, acrylic monomer, isooctyl acrylate, octyldecyl acrylate, tridecyl acrylate, caprolactone acrylate, ethoxylated 4-nonyl phenol acrylate, isobornyl acrylate, cyclic trimethylolpropane formal acrylate, methoxy polyethylene glycol (350) monoacrylate, 2-Propenoic acid, octadecyl ester, alkoxylated tetrahydrofurfuryl acrylate, alkoxylated phenol acrylate, 1,4-Butanediol Monoacrylate, benzyl acrylate, aliphatic urethane. Acrylate, 4-t-butylcyclohexyl acrylate, dioxolane Acrylate, 3, 3, 5-trimethyl cyclohexyl acrylate, benzyl acrylate, nonyl phenol (4EO) acrylate, phenol (2,5 EO) acrylate, 2-(butylaminolcarbnyl)oxylethyl acrylate, and octyldecyl acrylate.
A nonlimiting list of difunctional monomers include cyclohexane dimethanol diacrylate, alkoxylated hexanediol diacrylate, alkoxylated hexanediol diacrylate, alkoxylated hexanediol diacrylate, 1,10-decanediol diacrylate, acrylate ester, alkoxylated neopentyl glycol diacrylate, 1,3-butylene glycol diacrylate, 2-propenoic acid, 1,4-butanediyl ester, diethylene glycol diacrylate, 1,6 hexanediol diacrylate, neopentyl glycol diacrylate, polyethylene glycol (200) diacrylate, tetraethylene glycol diacrylate, triethylene glycol diacrylate, tripropylene glycol diacrylate, methypentanediol diacrylate, polyethylene glycol (400) diacrylate, ethoxylated (3) bisphenol a diacrylate, dipropylene glycol diacrylate, alkoxylated hexanediol diacrylate, ethoxylated (4) bisphenol a diacrylate, ethoxylated (10) bisphenol a diacrylate, polyethylene glycol (600) diacrylate, tricyclodecane dimethanol diacrylate, propoxylated (2) neopentyl glycol diacrylate, ethoxylated (30) bisphenol a diacrylate, alkoxylated aliphatic diacrylate, 1,9-nonanediol diacrylate, hexanediol (2 EO) diacrylate, and hexanediol (2 PO) diacrylate.
Due to recent changes in international regulatory rules, most of the key monomers used in energy cure chemistry can no longer be used in ink and coating formulation, and those which can be used do not perform adequately, i.e. they do not perform well with regard to surface cure, adhesion, flexibility, etc. Further, with the advent of environmentally friendly UV LED type curing lamp technologies, traditional UV monomers and oligomers cannot cure efficiently, resulting in incompletely cured inks and coatings. Innovation around formulations and raw materials for UV curable inks and coatings is desperately needed.